This invention relates to electronic warfare systems and specifically to a distributed electronic warfare system.
The DoD currently has very limited radio tactical intercept, geolocation, and electronic attack assets. National space borne assets are of limited value in hunting and closely locating targets in a confined geographic area such as Afghanistan. Assets high in orbit have a very narrow angle within which to identify targets, although they likely can hear them well. Attacking targets electronically from orbit is similarly difficult because of the path loss due to distance, complicated by the collateral damage from the wide orbital field of coverage. These issues are not unlike those arguments of imagery from orbit versus tactical low altitude.
Tactical electronic warfare assets today consist of the US Navy EA-6B Prowler fleet and a relative handful of special purpose aircraft such as the EC-130 Compass Call, Senior Scout, and Rivet Joint. The dedicated EW mission EF-111 fleet was retired years ago, ceding the major tactical EW support mission to the US Navy. Today the EA-6B is aging and in need of replacement. A valid question is whether the US Navy with its unique basing and support requirements is best suited to provide DoD tactical EW support for ground combat, especially far from the oceans, given that the Air Force is already providing other military assets and support in theater. A unique tactical EW aircraft is very expensive to develop, field and support.
Electronic warfare pods such as the AN/ALQ-167(V) and the self protect electronic countermeasures (ECM) pod AN/ALQ-184 are used on such aircraft as the F-16, A-10, F4, F-111, F-15, A-7, C-130, and EA-6B. These pods are typically used for tactical self-protection and standoff escort jamming and interfacing to ESM equipment. These electronic warfare pods do not provide the full tactical electronic warfare capabilities of a tactical EW aircraft such as radio intercept, geolocation, and electronic attack.
What is needed from tactical, strategic, and budgetary standpoints is an EW capability that can be fielded and operated as a transparent, standalone system on any random mix of aircraft and sorties in a theater of interest.
A distributed electronic warfare system is disclosed. The distributed electronic warfare system comprises a central control site for controlling the system and receiving data from the system. Electronic warfare pods are attached to aircraft for listening to targets and jamming the targets under control of the central control site and for supplying the data to the central control site.
A satellite communications system is utilized for communications between the electronic warfare pods and the central control site. The satellite communications system comprises a satellite communications network with a plurality of satellites, a ground network that supports and controls the satellite communications network, gateways for communicating between the satellites and a telephone network, and satellite system transceivers installed in the electronic warfare pods for communicating with the control site over the satellite communications network.
The electronic warfare pods further comprise antennas for radiating jamming signals to the targets and receiving signals from the targets, transmitters for generating the jamming signals, receivers for receiving the signals from the targets; and a signal processor for processing the received signals from the targets.
The electronic warfare pods perform search and collection of signals from targets using the plurality of receivers and the antennas on the pods. The receivers instantaneously span a portion of a band. The signal processor is connected to the receivers for performing a fast Fourier transform that is statistically blended into a search database to detect new energy. The presence of new energy is reported to the central control site via the satellite communications system.
The electronic warfare system may be programmed to search specified channels and the receiver outputs are applied in parallel to a delay line. The delay line output is compared to a current output of the specified channel to detect a new target signal.
Each pod may be programmed by the central control site with search and collection instructions via the satellite communications system. Each pod may be programmed independently or to operate in groups where all pods in the group are programmed identically and execute their commands in GPS time synchronization.
Geolocation of targets is determined by time difference of arrival of signals at a number of pods simultaneously. The geolocation is performed by transmitting from each pod in the group a precise GPS time-stamped sample file with a GPS location of each aircraft to the central control site. A correlation program at the control site determines the target signal geolocation from the time difference of arrival of the signals at each of the dispersed pods.
The pods may perform electronic attack by transmitting a radio signal using the transmitters and antennas to disrupt, deny or deceive an enemy target. The radio signal is transmitted on a selected frequency with a selected modulation under command of the central control site or a control site-initiated autonomous reactive jamming mode. Positive command and control of the electronic warfare system is obtained by transmitting a deadman command via the satellite link and with carrier lock of the satellite link. If the deadman command is missed or the satellite downlink signal is lost, the electronic attack is disabled and operation is resumed when the downlink signal and deadman command are reestablished. The jamming of the target may be reactive, blind, or barrage jamming. Modulations are from a preprogrammed waveform library downloaded via the satellite communications system or played back from a prior pod recording of the target. Deception of a target is typically achieved by playing back a selected digital file from the same target.
It is an objective of the present invention to provide a distributed electronic warfare system that can be fielded and operated as a transparent, standalone system on any random mix of aircraft and sorties in a theater of interest.
It is an objective of the present invention to provide an alternate means of implementing a tactical distributed electronic warfare system without the need for dedicated aircraft.
It is an advantage of the present invention to use a standard missile body as an electronic warfare pod.
It is an advantage of the present invention to perform search and collection, geolocation, and electronic attack from an electronic warfare pod.
It is an advantage of the present invention to utilize a satellite communications system to provide world-wide coverage of the distributed electronic warfare system.
It is a feature of the present invention to be able to mass more jamming power on a target than is possible from a single jammer where the target realizes the vector sum of all incident power from all jamming sources.
It is a feature of the present invention that an electronic warfare pod does not require control, input/output, or interactions with an aircraft upon which the pod is mounted.